The incident happened on Tuesday as the model turned animal rights activist attempted to deliver a People For The Ethical Treatment Of Animals (PETA) DVD showing creatures being killed for fur to Lopez, following a demonstration at which the 37-year-old pleaded with fans to boycott the superstar's music, movies and clothes because she uses fur in her fashion range, Sweetface.

After striding into the building opposite Manhattan's Bryant Park, accompanied by an entourage of journalists and photographers, McCartney Mills - who lost a leg after being hit by a car in 1993 - was confronted by burley minders who yelled: "You have no authority to be here.

"Get out! Leave the floor immediately!"

In the tussle that ensued, Mills McCartney's prosthetic leg became detached. She bent down and clutched her knee in pain, before asking to use a bathroom so she could reattach the leg.

Guards refused and she was forced to cling onto a photographer as she carried out the humiliating task on a stairwell.

Photographer Richard Corkery tells 25hoursonline.com: "I saw her touch her knee and I could see she was in pain. She limped to the ladies room but it was locked. I found another door open. It led on to the stairwell. At least she could have a private moment, which is what she needed."

According to 25hoursonline.com, Lopez's guards continued to verbally attack the group – screaming: "Call the cops! Call the cops!" - until Mills McCartney recovered her composure and was able to leave the building.